"If you can keyframe it, chances are you can control it with an expression, or use it as part of another property’s expression – usually by dragging the pick whip to it. However, there are additional properties you have access to – including those you can’t access with a pick whip, such as whether a layer’s audio or video switches are on, or its current in or out point. You’ll need to either manually type in code to access these, or get some help from the expression language menu. To give you a taste for what’s possible, let’s discuss a couple of comp and footage attributes of interest."Read more...